intake tricks produce horse power

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Raider L

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I've had one of these on my carb since about a year after they came out. The manf. says they will produce 10 to 15 horse power. But to be fair, even though some knot heads have tested it on a flow bench and said otherwise. Well, I'm sure their test was wrong but I can guarantee you it does produce horse power from the fact that physics is on it's side. I don't have a drag car to test out a open carb and one with this product on it so I can't say I've tested it on the strip. Unfortunately none are made for the Q-jet but there are plenty for all kinds of Holley carbs. There is one for a Carter AFB so if you have one of them I've included the number.

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K & N "stub stack" It's designed to smooth out the airflow into the carb. As you know there are all kinds of obstructions around the air horn for air to get down into the engine and this item smooths all the air flow out thus producing horse power, because the air goes straight in with no turbulence. This also helps alot in improving gas milage as well! This is the one I have on my engine and it's part number is:
K & N 85-200 for Holley 4150 and 4160 4 bbl. $54.99 (Summit price)

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Here's how it sits over the carb air horn. It's made so it sits snugly over the horn so you don't have to ever worry about it coming loose inside the air cleaner. It slides down over the center bolt for the air cleaner and the bowl vents.

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Another angle.

The part number for the Carter AFB is K & N 85-0700 $54.99 (Summit price)
 

SirRobyn0

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I have often thought this. My truck has an edlebrock on it that the former owner installed, though I prefer Q-jets, I fixed up the linkage early on the fuel line has been changed and there is a regulator for the edlebrock, so I've kept it so far at least. But he didn't install a intake he just used an adaptor plate on the factory manifold. I sometimes wonder how much power that adaptor plate robs.

Interesting idea on the stub stack.
 

Raider L

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@SirRobyn0,

Yeah, although the Edlebrock is basically a Q-jet, it's got so much stuff on top that is sticking up and moves that there's just no place to put something over the top to smooth out the airflow. You get whatever you get. And like some Holley's there are times when the linkage needs adjusting. I've never fooled with mine, I'd have to find the papers on my Holley to see what and where I'd check to see if it's off. I suppose I should do that from time to time. But I don't go jerking my carb around like happens when people race these things.

You have a regulator on your carb? How much pressure is it turned to? Do you have a fuel pressure gauge on your truck? Get a splitter and put a fuel pressure gauge on it so at least when you have the hood up with the motor running you can look down and see what your fuel pressure is. It might be to high, or to low. My fuel pump is a race pump regulated for 110 gal. per hour at up to 8 lbs. pressure. Like at low engine speed it might be pumping 6 lbs.. Then as I speed up it'll pump according to what the engine needs up to 8 lbs.

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This is the splitter I was talking about. I made that bracket that's holding it up out of 1/8" X 1" Alum. flat bar I got from Lowe's. The thing on the left of the splitter is the micron inline filter and it's hose comes from the fuel pump, the hose at the top goes to the carb., the hose at the bottom goes to the fuel pressure isolator that sends pressure readings inside the cab. The race rules say you can't have fuel inside with you, duh, the isolator has Anti Freeze in the hose that goes inside the cab.

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This is the pressure isolator made by Auto Meter. The hose on the left comes from the splitter, and the one in behind the isolator goes to the cab and has anti freeze in it. That's the way it comes, I don't know why they choose anti freeze but it is that way. That little screw above the hose in front lets air out of the line if you have to undo it for whatever. I made that little bracket out of 1/8" X 1" Alum. flat bar I got from Lowe's.

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When I started showing my truck after it was built people would ask me why I had two fuel gauges. I'd have to get them to read the gauge on the left because it says "fuel pressure" and doesn't have a 'E" or a "F" on it. lol
 

Turbo4whl

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When I started showing my truck after it was built people would ask me why I had two fuel gauges. I'd have to get them to read the gauge on the left because it says "fuel pressure" and doesn't have a 'E" or a "F" on it. lol

Just tell them that is the gauge for the reserve tank. :D
 

Rusty Nail

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Nah...those things are junk.
Dude don't know what he's talkin bout!

See?

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Performance.Airhorn.:headbang:
Ungh.
 

SirRobyn0

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@Raider L I'm running a used regulator and gauge I bought used from someone on the forum, I think it might be Holley brand but not sure. One of several downsides to the Edelbrock is that they don't like to much pressure. Edelbrock states no more than 6.5psi, but it seems like some guys still have issues at that pressure. I'm running my regulator set to 3.5PSI. I arrived at that number by slowly turning down the regulator until I had issues which was at about 3PSI, and I just set it for 1/2 psi higher. Only gauge is under the hood. Runs great like that so I'm good with it for the most part.

I have the factory air cleaner housing adapted to the edelbrock and the pressure regulator and gauge is tucked under that. I can see the gauge from the passenger side without taking anything off, but the idea is for it to not look modified.

Picture below. Pretty hard to tell there's an edelbrock under there. You can kind of see the corner of the fuel pressure regulator just to the right of the pre-heater tube.
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I've thought about going to an aluminum Edelbrock intake to get rid of the adaptor plate, I bet if I painted it GM blue, it wouldn't be to obvious. I've got some interior pics somewhere, if I can I'll dig those up this evening and tell you about what I've got going on in there.
 

SirRobyn0

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I don't have a stubstack and I'm not going to test drive one for $54, so I have no personal experiance. On the other hand if someone wanted to donate one to me for an Edelbrock, I'd be happy to try it and give my take. For me I think my biggest flow issue intake wise is the edelbrock to factory manifold adaptor.
 
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Raider L

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@SirRobyn0,

Yeah, I see it peeping out from there. You are able to find that silver corrugated aluminized hose thing going to that short pipe on the air cleaner horn? I couldn't ever keep mine from getting dented and mashed on the end that slides up on the little tube on the air horn, so I finally chunked it!

Aren't Edelbrocks "spread bore" carb's? What do you mean an adapter plate? You mean a spacer, a Aluminum or phenolic spacer under the carb.? Do you think it's leaking past the base of the carb or below it between the spacer and the mounting surface of the intake manifold? It could be leaking there. Did you put a gasket between the "adapter plate under it against the intake, and another one above it just under the carb.? You can't rely on the surface being perfectly flat, you have to gasket all of it. I have a 1/2" phenolic spacer under my carb and a gasket under it against the manifold and one on top of it under the carb.

Unlike the Edelbrock the only place a Holley can leak is at the shaft that runs through the carb base with the venturi plates on it. The holes running through the base wear out and air leaks at the shaft holes. Of course not withstanding any gasket leaks, the base plate shaft and holes is about it. I used to overhaul Carter AFB's and Q-jets and even a few Thermoquads, but that was a long time ago.
I do know they are very sensitive with vacuum leaks. If you have any it wants to run crappy. And there are alot of places for them to leak to. To many moving parts. Holley's are just simpler.
 
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Raider L

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@Rusty Nail,

That's it. I can see the claims K & N makes about the horse power gains satisfy the "physics of hydraulic flow coefficients". lol I don't even know what that means. Sounds good though. But they do smooth the air flow out and with all the junk on top of a Holley it just has to work. A Q-Jet is much worse with stuff on top the air has to find a way around and over to get down the carb into the intake. You don't want tubulence and obstructions which cause the air to have to stop and find another way in. Or it doesn't find a way in until later and is mixed with other air that is trying to find it's way in as well. You put that stack on and now there is nothing in the way but down the hole straight into the intake. You want smooth and fast air flow.
That's why you see race carbs, i.e. Holley's with everything milled off the top until there's nothing in the way of the air.
Some years ago I got to talk to Tony Christian world champ Super Stock drag racer, and he was running, at that time, two 1050 cfm Holley's on his big block. And looking down the throat of those monsters was like looking into a couple of 55 gal. drums. I asked him does it look like two fire hoses pouring gas down those things when you floor it and he said, "Yes, that's exactly what it looks like."
Dang! I love that kind of stuff!
 

SirRobyn0

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@SirRobyn0,

Yeah, I see it peeping out from there. You are able to find that silver corrugated aluminized hose thing going to that short pipe on the air cleaner horn? I couldn't ever keep mine from getting dented and mashed on the end that slides up on the little tube on the air horn, so I finally chunked it!

Aren't Edelbrocks "spread bore" carb's? What do you mean an adapter plate? You mean a spacer, a Aluminum or phenolic spacer under the carb.? Do you think it's leaking past the base of the carb or below it between the spacer and the mounting surface of the intake manifold? It could be leaking there. Did you put a gasket between the "adapter plate under it against the intake, and another one above it just under the carb.? You can't rely on the surface being perfectly flat, you have to gasket all of it. I have a 1/2" phenolic spacer under my carb and a gasket under it against the manifold and one on top of it under the carb.

Unlike the Edelbrock the only place a Holley can leak is at the shaft that runs through the carb base with the venturi plates on it. The holes running through the base wear out and air leaks at the shaft holes. Of course not withstanding any gasket leaks, the base plate shaft and holes is about it. I used to overhaul Carter AFB's and Q-jets and even a few Thermoquads, but that was a long time ago.
I do know they are very sensitive with vacuum leaks. If you have any it wants to run crappy. And there are alot of places for them to leak to. To many moving parts. Holley's are just simpler.
No the edelbrock is a square bore, so must have an adaptor. The Q-jet and factory manifold are spread bore. No vacuum leaks for me. I have a thick gasket between the manifold and the adaptor and a phenolic spacer with gaskets between the top of the adaptor and the edelbrock because edelbrock performers are notorious for percolating the gas in the float bowl after shut down, mostly only in extreme heat or in moderate heat if working the engine hard.

I do like the Q-jet, I'm not really an edelbrock fan, but I can see why guys like them because they are simple and easy to work on. Really the only reason I've kept the edelbrock is the former owner put it on shortly before he passed and it was a new carb. He didn't have a lot of stuff set up right so I did have to do somethings to get it working right. FYI if you didn't know the edelbrock is a Carter AFB, the later style AFB that is, it is not a Q-jet.

That aluminum tube is called a pre-heater tube. I like to keep the end on the manifold clamped on, and the air cleaner end just slipped over the tube, so if I forget about it I don't stretch it out or stretch it and smash it.
 

82sbshortbed

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With that on there you should try and add this also and bet you could tell even better throttle response. CoggedBelt75 put some on his truck and said he could tell a difference in his.

https://thompsonperformance.com/

Better airflow plus a finer spray has to mean better right?? I would think so.
 

emoze

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fascinating - ya gotta wonder why K&N would market such a thing if they knew it was useless?

vs a no-name from China i would understand
 

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I have some big doubts on whether it does anything at all to add any kind of performance gain. Physics is not really in it's favor, regardless of what K&N would have you believe. In fact, turbulence at the venturi and in the intake manifold in general(at the tube walls) helps the fuel to mix and atomize with the air.

I'm thinking they are trying to say that the smooth transition helps the air to have a higher velocity when it goes through the venturi, which is not really how that works. We could get into some numbers and math on this, but as I've been told before on here, "that's nerd stuff" and probably not that interesting of a discussion for non-engineer types. Ultimately, my gut feeling is the marginal improvement in velocity you might get from this may or may not have any effect on overall engine efficiency or performance. It probably depends very heavily on your specific engine setup, and might even hurt performance in some applications.

I love these "performance parts" that have some completely useless statement like "physics of hydraulic coefficients".. lol. Always makes me think of this video.

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Gotta love those Turbo-Encabulators!
 

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